Assumptions about future events are a necessary component of the
actuarial valuations. Key among them are:

• Members' future rates of retirement and disability.

• Their total length of service.

• The rate at which their salaries will increase.

OSA performs experience studies at least once every six years to determine at what rate the above factors have actually occurred in the retirement systems. We
compare actual rates to the assumptions and, if necessary, we make adjustments to the rates for future valuations.